Only one, either DCC or Fees could possibly be active at any given time. Since both fields are optional, if you specify a value for either where that feature is not enabled, it will be ignored. Thus, whichever feature is enabled is what will be applied in this case. In fact, if neither DCC nor Fees are enabled for the terminals, then BOTH would be ignored.

Please note the following for CSV file upload:

Passing the “DCC Opt-In” property (key) is optional. However, if the “DCC Opt-In” key is being passed, then the value pair field must have the “Y” or “N” indicator. If NO “DCC Opt-In” property(key) is passed, then the default value assumed is "N".

If the merchant uploads a CSV File with the “DCC Opt-In” field set to “Y” and DCC has not been enabled on their account then the transaction(s) will fail.

Passing the "DCC Opt-In" property is optional. In the case of no "DCC Opt-in" property (key) being passed, the default value pair would be "N".

Only one, either DCC or Fees could possibly be active at any given time. Since both fields are optional, if you specify a value for either where that feature is not enabled, it will be ignored. Thus, whichever feature is enabled is what will be applied in this case. In fact, if neither DCC nor Fees are enabled for the terminals, then BOTH would be ignored.